Stool



FIG. 1 is a front three-quarter perspective view of my design;

FIG. 2 is a plan view;

FIG. 3 is a view of front elevation;

FIG. 4 is a view in side elevation, being a view from the right aspect of FIG. 2;

FIG. 5 is a view in rear elevation; 

The ornamental design for a stool, substantially as shown and described. 